This invention relates to a system for dispensing soap with a wide range of viscosities. Although the invention may be used to dispense a wide variety of viscous material, soap will be used for only illustrative purposes. Normally, soap is dispensed in commercial systems wherein the soap has a relatively low viscosity on the order of 1000 to 2000 cps. The present invention is directed toward a system which can accommodate the lower viscosity soaps normally encountered in commercial establishments such as restaurants, washrooms, airports, and the like, as well as grit containing soaps in which the viscosities may be as high as 20,000 cps.
Patents which are relevant to the lower viscosity dispensing systems, for instance, include but are not limited to U.S. Pat. Nos. Des. 248,927, Des. 278,887,Des. 282,347, Des. 282,528, Des. 299,427, Des. 325,312, Des. 332,544, 4,149,573 , 4,173,858, 4,214,676, 4,316,555, 4,391.308, 4,391,309, 4,429,812, 4,673,109 , 4,886,192, 5,082,150, 5,174,476, 5,209,377, 4,345,627, and 4,576,313.
On the other hand, when viscosities increase, systems such as those disclosed in the patents above are often insufficient to dispense the higher viscosity material. Frequently, higher viscosity materials on the order of 15,000-20,000 cps viscosities simply do not flow through the systems used to dispense soaps having viscosities in the 1000-2000 cps range. Accordingly, this invention is directed to a new system which can accommodate soaps having a wide range of viscosities.